code: def transform(
      self, X: list[Performance], _y: Any = None
  ) -> npt.NDArray[np.float32]:
      df = Performance.to_dataframe(X)
      return df[self.feature_names_].to_numpy()
  
file_path: gluonts/src/gluonts/nursery/tsbench/src/tsbench/surrogate/transformers/performance.py
imports: from __future__ import annotations
  from typing import Any, List, Optional
  import numpy
  import numpy.typing
  import pandas
  from sklearn.base import TransformerMixin
  from tsbench.evaluations.metrics import Performance
label_desc: Use image node_id 3 for calling the PerformanceEncoder obj's underlying member method code with example usage: obj.transform(X, _y) and returns: df